Embodiments of the present disclosure relate generally to biological or chemical analysis and more particularly to systems and methods using detection devices for biological or chemical analysis.
Various protocols in biological or chemical research involve performing a large number of controlled reactions on local support surfaces or within predefined reaction chambers. The desired reactions may then be observed or detected and subsequent analysis may help identify or reveal properties of chemicals involved in the reaction. For example, in some multiplex assays, unknown analytes having identifiable labels (e.g., fluorescent labels) may be exposed to thousands of known probes under controlled conditions. Each known probe may be deposited into a corresponding location on a surface. Observing any chemical reactions that occur between the known probes and the unknown analyte on the surface may help identify or reveal properties of the analyte. Other examples of such protocols include known DNA sequencing processes, such as sequencing-by-synthesis (SBS) or cyclic-array sequencing.
In some conventional fluorescent-detection protocols, an optical system is used to direct an excitation light onto fluorescently-labeled analytes and to also detect the fluorescent signals that may emit from the analytes. The resolution of standard imaging techniques is constrained by the number of pixels available in the detection device, among other things. As such, these optical systems can be relatively expensive and require a relatively large bench-top footprint when detecting surfaces having large collections of analytes. For example, nucleic acid arrays used in genotyping, expression, or sequencing analyses can require detection of millions of different sites on the array per square centimeter. Limits in resolution increase cost and decrease accuracy of these analyses
Thus, there exists a need for higher resolution apparatus and methods, for example, to detect nucleic acid arrays. The present disclosure addresses this need and provides other advantages as well.